It is unclear how some non-textile fabrics are formed into the desired two-dimensional or three-dimensional final shapes. In particular, it is unclear how the edges of the material are attached along seams in a manner that is economical, strong, and maintains the benefits of the non-textile fabric structure (such as cut and pierce resistance). One way to physically cut the two-dimensional fabric into the desired shape is by an industrial shear, laser, or other conventional industrial cutting process. However, it is believed that such a process would make it difficult, if not impossible, to then attach that cut edge to another piece of textile fabric in an economical way and maintain the benefits of the non-textile fabric. One such way to attach the rough-cut edges would be to use traditional zipper technology. However, while this allows separate pieces of non-textile fabric to be attached together, it does not provide a seam that maintains the benefits of the non-textile fabric.
In the application of the non-textile fabric to luggage, the use of a clamshell opening frame instead of a conventional zippered opening frame would avoid the security issues of using conventional zippers. However, neither of these methods takes advantage of the inherent characteristics of the non-textile fabric.
Further, when considering the attachment of the fabric materials along the seams, it is also important to consider the interconnection between elements not at the seams to insure that the seam does not fail at a significantly different load than the inter-plate connection. In known elements for non-textile fabrics, there are shapes or structures along the edges of the elements that mechanically interconnect with a corresponding or complementary shape of an adjacent element. Thus these interconnecting shapes hold adjacent elements to each other, and thus these connection shapes hold the overall fabric together. When a tensile force is applied to the assembled fabric, these shapes can distort in response to the stress.
For example, in the metal plate and ring type chain mail fabrics characterized Whiting & Davis bags and fashion items, such tensile stress tends to unclench the small metal hooks formed at the corners of the metal plates which engage the metal rings arrayed between the adjacent plates. In this example, the tensile force in fabric results in a bending force on the hooks. The mode of failure, when the tensile force in the fabric is exceeds a certain amount, is usually the straightening of the hooks, which thus slip out of engagement with the rings.
In the non-textile fabrics according to U.S. Pat. Nos. 5,853,863 and 5,906,873, the likely failure mode in this tensile overstress scenario is bending or stretching the rivet shaft to where the hooked edges of the plates slip past one another.
The barb and socket interconnecting plates described in the U.S. patent application incorporated by reference above, while less likely to fail prematurely because of yielding at the interconnecting shapes, will likely still fail when the socket portion spreads by bending, thus letting the barbed portion slip out.
In all of these cases, the interconnecting shapes tend to be the “weak link” in the system. Thus, the object of this invention is to strengthen the interconnecting shapes so as to delay or prevent premature disconnection of the adjacent elements when under normal to high tensile loads.
It is with these shortcomings in mind that the instant invention was developed.